Photographic color reproduction process and element



Jan. 4, 1966 FIG. I

FIG. 2

K. E WHITMORE ETAL 3,227,550

PHOTOGRAPHIC COLOR REPRODUCTION PROCESS AND ELEMENT Filed Sept. 7, 1962 /TOPCOAT PROTECTIVE LAYER BLUE SENSITIVE EMULSION YELLOW-FORMING COUPLER INTERLAYER GREEN SENSITIVE EMULSION MAGENTAFORNIING COUPLER INTERLAYER RED SENSITIVE EMULSION CY ANFORMING COUPLER SUPPORT TOPCOAT PROTECTIVE LAYER BLUE SENSITIVE EMULSION YELLOW- FORMING COUPLER INTERLAYER GREEN SENSITIVE EMULSION MAGENTA-FORMING COUPLER INTERLAYER RED SENSITIVE EMULSION CYAN-FORMING COUPLER STRIPPING LAYER 2| /-MORDANTED RECEPTION LAYER 20 SUPPORT IN VEN TORS BY iw/M SEQ/hi ATTORNEYS KEITH E. WHITMORE United States Patent 3,227,550 PHOTOGRAPHIC COLOR REPRODUCTION PROCESS AND ELEMENT Keith E. Whitmore and Paul M. Mader, Rochester, N.Y.,

assignors to Eastman Kodak Company, Rochester,

N.Y., a corporation of New Jersey Filed Sept. 7, 1962, Ser. No. 222,105 Claims. (Cl. 96-3) This application is a continuation-in-part application of copending US. Serial No. 734,141 filed May 9, 1958 (now abandoned), and US. Serial No. 756,597 filed August 22, 1958 (now abandoned). U.S. Serial No. 734,141 in turn is a continuation-in-part application of US. Serial No. 570,179 filed March 7, 1956, now abancloned.

This invention relates to color photography, and more particularly, to photographic color difiusion transfer processes and photographic elements suitable for use in such processes.

Photographic color processes are well known in the art. A typical color process comprises the reaction of color couplers with oxidation product of an aromatic primary amino color developing agent to form insoluble image dyes in the areas of development. Color processes are also known whereby color images are transferred to receiving elements, and which have the advantage of producing color images free of residual color couplers and other products of development. However, many of such processes of the latter type involve several complex steps, require several processing baths with large volumes of processing solutions, and produce poor quality color images due to lateral diffusion of dye-forming components.

It is an object of the present invention to provide a new color process in the photographic art.

It is another object of this invention to provide a new photographic process for producing particularly sharp color images.

It is another object of this invention to provide a novel photographic diffusion transfer process wherein a dye image is transferred to a receiving layer.

It is another object of this invention to provide a novel color diffusion transfer process that can be effected in one wet processing step.

It is another object of this invention to provide a novel color diffusion transfer process wherein the color development is carried out in the presence of a predominant proportion of the products of oxidation of the color developing agent.

It is still another object of this invention to provide a novel process for preparing direct positive color images.

It is also an object of this invention to provide a novel color difiusion transfer process for producing direct posi tive full-color images.

It is likewise an object of this invention to provide a novel photographic element suitable for use in preparing color images by a photographic diffusion transfer process.

These and other objects are attained by means of this invention as described hereinafter with reference to preferred embodiments thereof.

The present invention concerns the processing of photographic elements having superposed thereon red, green and blue light sensitive hydrophilic colloid silver halide emulsions with developable patterns in the silver halide, there being disposed integral with the element and contiguous to the emulsions a cyan-forming coupler, a magenta-forming coupler and a yellow-forming coupler. The incorporated couplers are nondiffusible during development in the presence of an alkaline color developing solution containing an aromatic primary amino color developing agent and are preferably capable of forming dilfusible acid dyes complementary to the color of the spectral sensitivity of the respective contiguous light-sensitive emulsions. In the present process, the color developing of the silver halide emulsions is carried out with an alkaline color developing solution containing an aromatic primary amino color developing agent. During the color developing, the non-diifusible couplers react with oxidation product of the color developing agent to release diffusible acid dye images in areas of color development, and the resulting dye images diffuse imagewise in register to a juxtaposed reception layer containing a mordant for acid dyes.

When conventional silver halide negative emulsions are used in the photographic elements, negative transfer images can be produced. Photographic elements containing such conventional silver halide emulsions can also be utilized to prepare positive transfer images by subjecting the element to an initial black-and-white development to develop the exposed areas of the emulsion and thereafter rendering the resulting unexposed and undeveloped areas of the emulsions developable by flash exposure or chemical fogging in the usual manner prior to the color development. Also positive transfer images can be obtained with a single development in the color developer by utilizing direct positive silver halide emulsions such as internal image emulsions or solarizing emulsions.

The color couplers used in the photographic elements of the invention are initially nonditfusing in photographic silver halide emulsions but form diffusible dyes on development witharomatic primary amino silver halide photographic color developing agents such as p-phenylenediamine developing agents. Such color couplers include those having the formulas:

(1) DYE is a dye radical containing an acidic solubilizing radical;

(2) LINK is a connecting or linkage radical such as azo mercuri (Hg), oxy (O-), alkylidene (includes both CH- and =CH), thio (-S), or dithio 0 (3) COUP is a photographic color coupler radical such (4) BALL is a photographically inert organic radical of such molecular size and configuration as .to render the coupler nondiftusing in the alkaline color developing solution;

(5) SOL is either a hydrogen atom or an acidic solubilizing group when the color developing agent contains an acidic solubilizing radical, SOL always being an acidic solubilizing radical when the color developing agent is free of an acidic solubilizing group; and

(6) n is integer of 1 to 2 when LINK is an alkylidene radical, and n is always 1 when LINK is one of the other aforementioned connecting radicals, namely, azo, azoxy, mercuri, oxy, thio, or dithio.

The acidic solubilizing radicals attached to the difusible dye-producingcouplers described above can be solubilizing radicals which when attached to the coupler or developer moieties of the dyes, render the dyes difiusible in alkaline processing solutions. Typical of such radicals are carboxylic, sulfonic, ionizable sulfonamido, and hydroXy-substituted groups that lend to dyes negative charges.

The nature of the ballast groups in the dififusible dyeproducing coupler compounds described above (BALL) is not critical as long as they confer nondifiusibility to the coupler compounds. Typical ballast groups exemplified hereinafter in the specific couplers disclosed include long chain alkyl radicals linked directly or indirectly to the coupler molecules as well as aromatic radicals of the benzene and naphthalene series, etc., linked directly or indirectly to the coupler molecules by a splittable linkage, or by a removable or irremovable but otherwise nonfunctional linkage depending upon the nature of the coupler compound. Useful ballast groups have at least 8 carbon atoms.

Typical dye radical substituents (DYE-) include azo, azomethine, indoaniline, indophenol, anthraquinone and related dye radicals well known in the art that exhibit selective absorption in the visible spectrum. The dye radicals contain acidic solubilizing moieties.

With regard to the above-described coupler radicals (COUP-), the coupling position is well known to those skilled in the photographic art. The S-pyrazolone coupler radicals couple at the carbon atom in the 4'- position, the phenolic coupler radicals, including a-naph thols, couple at the carbon atom in the 4-position and the open-chain ketomethylene coupler radicals couple to the carbon atom forming the methylene moiety (e.g.,

* denoting the coupling position).

The term nondifiusing used herein asapplied to the couplers, has the meaning commonly applied to the term in color photography and denotes materials which for all practical purposes do not migrate or wander through organic colloid layers, such as gelatin, comprising the sensitive elements of the invention. The same meaning is to be attached to the term immobile.

The term difiusible as applied to the dyes formed from the nondifiusing couplers in the processes has the converse meaning and denotes materials having the property of diffusing effectively through the colloid layers of the sensitive elements in the presence of the nondifusing materials from which they are derived. Mobile has the same meaning.

The following are representative of the nondiifusible coupler compounds of the invention which release or form diffusible acid dyes on coupling with the oxidation products of color developing agents.

Couplers I to X below are substituted in the coupling position with preformed yellow dyes which are split from the ballasted couplers and become diffusible when said couplers react with oxidized color developers.

5 1 -hydroxy 4 {3-[4-(N-ethyl-N-jS-sulfoethylamino)-2- methylphenylazo] phenylazo} N [6-(2,4-di-tert-amylphenoxy)butyl]-2-naphthamide sodium salt.

conntcmn-o-Omma l5 C3H11t CsHi N=N N\ CzHisoaNa CH:

l-hy'droxy 4 {4-[l-(4-sulfophenyl)-3-methyl-4-pyrazol- S-onylazo] 3 sulfophenylazo}-N-[6-(2,4-di-tert-amylphenoxy)but'yl] -2-naphthamide disodium salt.

CONH(CH2)|-O-QO5H11(U 40 I V s uG) I'q l l CH: SO Na N=N-CH N-OSOaNa l-hydroxy 4-{3-[4-(N-ethyl-N-fi-carboxyethylamino)-2- methylphenylazo]phenylazo} N- [ii-(2,4-di-tert-amylphenoxy) butyl]-2-naphthamide sodium salt.

1-(p-t-butylphenoxyphenyl)3-[a-(4-t-butylphenoxy)- propionamido]-4- (2-bromo-4-methy1amino-5- sulfo-1-anthra-9,IO-quinonylazo) -5-pyrazo1one.

NHCH:

a-{3- oc- 2,4-di-tert-amy1phenoxy) acetamido] benzoy1}- lit-{3 [4- (N-ethyl-N-fi-sulfoethylamino) -2-methyl- 9 0 phenylazo]phenylazo}-2-methoxyacetani1ide sodium salt.

1-hydroxy-4-{4-[1-(4-su1fophenyl)-3-carboxy-4- pyrazol-S-onylazo] -3-sulfophenylazo} -N-{4- [a- (2,4-di-tert-amylphenoxy) butyramido] phenethy1}- 2-naphtharnide.

(X) 0 H C5 11t HgO COCuHz; 75

1-hydroXy-4-dodecyloxy-Z-naphthoic acid.

a Benzoyl u-[4-(3-rnethyl-5-pentadecyl)pyrazolylazo] 4-(3,5-disulfobenzamido)acetanilide dipotassium salt.

a Benzoyl u-(3-octadecylcarbamylphenylthio)-3,5-dicarboxyacetanilide.

(XLV) C O OH COOH --CONHC1s a1 Ix Pivalyl a-(3-octadecylcarbamylphenylthio)-4-sulfoacetanilide potassium salt.

Difiusible dyes are formed when the above listed (i.e., I to XLVI) non-diffusing couplers are employed in the process of the invention with well-known p-phenylenediamine developing agents, e.g., N,N-diethyl-p-phenylenediamine, Z-amino-S-diethylamino toluene, N-ethyl-flmethanesulfonamidoethyl 3 methyl 4 aminoaniline, and other N,N dialkyl p phenylene diamine developing agents described by Bent et al., J.A.C.S. 73, 3100-3125 (1951).

Couplers XLVII to LV are nondifiusible couplers which can also be used in the process of our invention when the color developing agent is supplied with the alkali solubilizing function.

Couplers XLVII to L below form diflusible cyan dyes.

(X L VII) H 1-hydroxy-4-dodecyloxy-Z-naphthanilide.

(XL VH1 1 6 1-hydroXy-4-(2-amino-4-octadecylphenylazoxy) -2- naphthamide.

(XLIX) OH CONH2 1-hydroXy-2,5'-dibutoXy-4-[4-(sulfomethyl)phenylazo] -2-naphthanilide.

Couplers LI to LIII below form diffusible magenta dyes. 1-phenyl-3-methyl-4-(4-octadecyloxybenzylidene)-5- pyrazolone.

N C-CHa 4,4-thiobis(1-phenyl-3-methyl-5-pyrazolone).

4,4-dithiobis 1-phenyl-3 -methyl-5-pyrazolone) Couplers LIV and LV below form diffusible yellow dyes.

a,tx- (4-octadecyloxybenzylidene)bis [a-benzoylacetanilide] I II HTOO olsHu a,a'-dithiobisbenzoylacetanilide.

Representative color developing agents possessing the solubilizing functions useful with the nonditfusing couplers above are as follows:

4-amino-N-ethyl-3-methyl-N- (fi-sulfoethyl )aniline 4-amino-N-ethyl-3-methoxy-N- B-sulfoethyl aniline 4-amino-N-ethyl-N- fi-hydroxyethyl) -aniline 4-amino-N,N-diethyl-3-hydroxymethyl aniline 4-amino-N-methyl-N- (B-carboxyethyl) aniline 4-amino-N,N-biss-hydroxyethyl) aniline 4-amino-N,N-bis [i-hydroxyethyl) -3-methyl aniline 3-acetamido-4-amino-N,N-bis (B-hydroxyethyl) aniline 4-amino-N-ethyl-N- (2,3-dihydroxypropyl) -3-methyl aniline sulfate salt 4-amino-N,N-diethyl-3- 3 -hydroxypropoxy) aniline When the coupler radical (COUP) in the above-described formulas is a 5-pyrazolone radical, we prefer to have substituted in the 3-position of the pyrazolone moiety an anilino group or an alkOXy group. When the coupler radical (COUP) is a cyan-forming phenolic coupler radical, we prefer to have substituted in the ortho or 2-position of the phenolic moiety a fully substituted amido group (e.g.

-COI I-R wherein R is an alkyl group or a phenyl group). Also, when the connecting radical (LINK) in the above-described formula, BALLLINK(COUP-SOL) is an azo radical, we prefer that the ballasting radical (BALL) be a phenyl radical containing either a hydroxy group or an amino group (NH substituted in the ortho or 2- position of the phenyl moiety.

For true sensitization, to wit, correct color rendition, in the images prepared with the photographic elements of the invention, the color of the preformed dye radical (DYE) in the above-described couplers is complementary to the color at which the silver halide contiguous to the coupler is sensitive. However, false sensitization can also be utilized in preparing the present photographic elements.

The following syntheses illustrate the methods for preparation of representative couplers of our invention.

COUPLER I 1 hydroxy 4 {3 [4 (N ethyl N ,8 sulfoethylamino) 2 methylphenylazo]phenylazo} N [6(2,4- d'i tert amylphenxy)butyl] 2 naphthamide sodium salt To 200 ml. of concentrated sulfuric acid at 10 C. was added with stirring 17 g. of Intermediate C below. To the resultant solution was added dropwise over a period of 30 minutes at C. with stirring a solution of 3.5 g. of sodium nitrite in 35 ml. of concentrated sulfuric acid (i.e. nitrosylsulfuric acid solution). This solu- 18 COUPLER I, INTERMEDIATE A N-ethyl 3 methyl N ([3-sulf0ethyl)aniline sodium salt. A mixture of 675 g. of N-ethyl-toluidine and 528 g. of sodium 2-bromoethane sulfonate was heated at 160190 C. for 3 /2 hours, after which time mixture was cooled and 1200 ml. of water was added. The solution was made alkaline with sodium hydroxide and the solid which separated was collected, washed with acetone and ether and recrystallized from 2.5 liters of ethyl alcohol, yielding 420 g. of product.

COUPLER I, INTERMEDIATE B- ;3 {N ethyl N [3 methyl 4 (3 nitrophenylaz0)phen5yl]amin0}ethylsulfonic acid sodium salt.-To .a solution of 27 g. of Intermediate A above in 250 ml. of water at 0 C. was added a chilled diazonium solution consisting of 14 g. of m-nitroaniline and 7.5 g. of sodium nitrite in 200 ml. of 6 N hydrochloric acid. The resultant mixture was neutralized to Congo red paper by the addition of sodium acetate. This mixture was chilled for 2 hours after which time the solid which separated was collected, washed with cold water, and recrystallized from 360 ml. of water, yielding a green product.

COUPLER I, INTERMEDIATE C fi-{N [4 (3 aminophenylazo) 3 methylphenyl1- N-ethylamino}ethyl sulfonic acid sodium salt.To a solution of 41 g. of Intermediate B above in 2 liters of Water at C. was added over a period of 30 minutes a solution of 40 g. of 60% sodium sulfide in 150 ml. of water. The mixture was refluxed for an additional 2 /2 hours during which time approximately /2 of the water was distilled off. This mixture was filtered and refrigerated over night during which time a solid separated. The solid was collected and recrystallized from 200 ml. of ethyl alcohol, yielding the product.

COUPLER VII 1 hydroxy-4-{4-[3-methyl-4-(1,5-disulf0-3-naphthylazo)- l pyrnzol-S-onyl]phenylaz0}-N-[6-(3-pentadecylphen- 0xy)butyl]-2-naphthamide disodium salt A solution of 6.5 g. of sodium nitrite in 93 ml. of water was added to a solution of 49.5 g. of Intermediate E below in 300 ml.) of five percent sodium carbonate solution. This mixture was cooled to 10 C., and added to a well-stirred mixture of 75 ml. concentrated hydrochloric acid and 150 g. of ice. After 1 /2 hours, the diazonium suspension was added in portions with vigorous stirring to a solution of 44.4 g. of Intermediate C below in a mixture of 1500 ml. of ethyl alcohol and 55 g. of potassium carbonate in 360 ml. water. After two hours, the crude product was filtered, triturated in boiling ethyl alcohol, then dissolved in 1500 ml. ethyl alcohol and 1500 ml. of 3% potassium carbonate solution. The dark orange solution was filtered and acidified with acetic acid. The solid which separated was filtered, triturated in acetone and benzene, extracted twice with hot water, and recrystallized from a 1:1 n-propyl alcohol-water mixture, yielding 40 g. of product, M.P. 270 C.

COUPLER VII, INTERMEDIATE A 'y-(3-penladecylphen0xy)butyr0nitrile.A mixture of 4 g. of sodium hydroxide and 31 g. of 3-pentadecylphenol (Minn. Mining and Mfg. Co.) in ml. of xylene was refluxed for 6 hours during which time 1.8 ml. of water was distilled off. To the mixture was added 11 g. of 7- chlorobutyronitrile dropwise over 1 hour after which time the mixture was refluxed for 7 hours. The xylene was then distilled off over a 12 hour period and the residual oil was poured into 25 ml. of dilute hydrochloric acid. The Waxy solid which separated was collected and recrystallized from 100 ml. of acetonitrile, yielding 23 g. of product, M.P. 46-47 C.

COUPLER VII, INTERMEDIATE B 8(3-pentadccylplzenoxy)butylamine.A mixture of 5 g. of Intermediate A above, 3 ml. of ethyl-alcohol, 5 ml. of liquid anhydrous ammonia and 0.1 g. of Raney nickel was heated for 12 hours at 100 C. under a hydrogen atmosphere at a pressure of 2200 p.s.i. The cooled solution was filtered and concentrated in vacuo. The residual oil was distilled at 165 C. at 9 microns, yielding the product.

COUPLER VII, INTERMEDIATE C I-hydroxy-N-[6-(3-pentndccylphenoxy) butyl] -2-naplztliamide-A mixture of 5 g. of phenyl l-hydroxy-Z-naphthoate and 7 g. of Intermediate B above was heated at 150 C. for /2 hour in vacuo during which time phenol was collected from the mixture. The residual oil was poured into 100 ml. of petroleum ether whereupon a crystalline solid separated. This solid was collected and re crystallized from 90 ml. of ethyl alcohol, yielding 8 g. of product, M.P. 64-66 C.

COUPLER VII, INTERMEDIATE D 1 (4-nitr0phenyl)-3-methyl-4-(1,5-disulfo-3-naphtlzylazo)-5-pyraz0l0ne disodium salt-To a solution of 2.8 g. of 1-(4-nitrophenyl)-3-methyl-5-pyrazolone, 0.5 g. of sodium hydroxide and 7 g. of sodium acetate in 40 ml. of water was added at 20 C. over a period of 20 minutes a diazonium mixture consisting of 1.1 g. of 2-amino-1,5- naphthalenedisulfonic acid disodium salt, 1.4 g. of sodium nitrite, 2 ml. of concentrated sulfuric acid and 10 ml. of water. The mixture was stirred for 1 hour at room temperature and heated over steam until all solids dissolved. The solution was cooled to 5 C. whereupon a red solid separated and was collected, yielding 4.5 g. of product.

COUPLER VII, INTERMEDIATE E 1 (4 aminophenyl) 3-methyl-4-(1,5-disulf0-3-naphthylaz)-5-pyraz0lone disodium salt.To a mixture of 31 g. of Intermediate D above in 32 ml. of water at 90 C. was added over a period of 20 minutes a solution of 18 g. of 60% sodium sulfide in 40 ml. of water. The mixture was heated at reflux for an additional 2 hours after which time it was cooled to 50 C. and acidified with acetic acid. The solid which separated was collected and recrystallized from 250 ml. of 10% brine solution, yielding 15 g. of product, M.P. 250 C.

COUPLER XI 1-lzydroxy-4-stear0yl0xymercuri-Z-naphthoic acid To a solution of 9.4 g. of l-hydroxy-Z-naphthoic acid (JACS 64, 799 (1942)) in 200 ml. of dioxiane was added a solution of 38 g. of mercuric stearate in 500 ml. of dioxane. The mixture was heated over steam for hours during which time a white solid separated. This solid was collected, washed with hot methyl alcohol and dried, yielding 30 g. of product.

COUPLER XII 1-hydr0xy-4-dodecyl0xy-2-naphth0ic acid 1-l1ydr0xy-N-(B-sulfoetlzyl) -4-(4-octadecyloxyphenylzrz0)-2-napl1tl1amide potassium salt To a solution of 51 g. of potassium hydroxide and 63 g. of Intermediate A below in 350 ml. of water and 1700 ml. of ethyl alcohol was added at 5 C. over a period of 1 hour, a diazonium solution consisting of 72 g. of Intermediate B below, 120 g. of p-toluene sulfonic acid, and 30 g. of isoamylnitrite in 2 liters of n-propyl alcohol. The mixture was stirred at room temperature for 5 hours after which time 3 liters of water were added and the mixture brought to reflux. The hot solution was filtered, acidified with glacial acetic acid and cooled whereupon a solid separated. The solid was collected, recrystallized from 1.5 liters of n-butyl alcohol, yielding g. of product, M.P. 22830 C.

COUPLER XV, INTERMEDIATE A 1 lzydroxy-N-(fl-sulfoethyl)-2-naphthamide potassium salt.A mixture of 132 g. of phenyl l-hydroxy-Z-naphthoate, 1 liter of ethyl alcohol, 57.5 g. of taurine, 300 ml. of Water and 28 g. of potassium hydroxide was refluxed for 15 hours after which time the solution was cooled and the solid which separated was collected, washed with ethyl alcohol, recrystallized from H 0 and dried, yielding 71 g. of product, M.P. 284286 C.

COUPLER XV, INTERMEDIATE B 4-0ctadecyl0xyaniline.A mixture of 39 g. of 4-nitrophenyloctadecyl ether (J.A.C.S. 73, 458 (1951)) and 0.5 g. of 10% palladium on charcoal in 300 ml. of ethyl alcohol was heated at 5 0 C. for /2 hour under a hydrogen atmosphere at a pressure of 50 p.s.i.

The catalyst was filtered from the hot solution which was then chilled whereupon a solid separated. This solid was collected, and dried, yielding 32 g. of product, M.P. 7881 C.

The preparations for couplers XVIII, XIX, XX, and XXI are given in copending application U.S. Serial No. 154,841, filed Nov. 24, 1961.

COUPLER XXIV 2-(3,5-disulf0benzamid0 -4-(4-lzydr0xy-2-pentadecylplzenylazo)-5-metlzylphen0l dipomssium salt To a solution of 21 g. of 2-(3,S-dichlorosulfonylbenzamido)-5-methylphenol in 50 ml. of pyridine and 10 ml. of water was added a diazonium solution consisting of 16 g. of 4-amino-3-pentadecylphenol, 7 g. of isoamylnitrite, and 10 ml. of concentrated hydrochloric acid in 100 ml. of n-propyl alcohol. The mixture was stirred at room temperature for 12 hours after which time it was poured into 400 ml. of saturated potassium chloride solution. The gummy solid which separated was collected, triturated twice in methyl alcohol and dried, yielding 11 g. of product.

COUPLER XXX 1 -plzenyl-3 3 -sulf0benzamid0) -4- 4-0ctadecyl0xyphenylazo) -5-pyraz0l0ne sodium salt To a solution of 3.6 g. of Intermediate B below and 2 g. of sodium hydroxide in 55 ml. of ethyl alcohol at 0 C. was added with stirring a diazonium solution consisting of 3.6 g. of 4-octadecyloxyaniline (Intermediate B of Coupler XV above) 5.7 g. of p-toluenesulfonic acid monohydrate and 1.5 g. of isoamylnitrite in ml. of n-propyl alcohol at 20 C. The mixture was stirred at room temperature for 3 hours after which time 25 ml. of water was added and the mixture was acidified with acetic acid. To this solution at 90 C. was added 100 g. of sodium chloride and the resultant solution was filtered and cooled. The solid which separated was collected, washed with water and dried, yielding 6 g. of product, M.P. 198-200 C.

COUPLER XXX, INTERMEDIATE A I plzenyl-3-(3-clzIorosulfonylbenzamido) 5 pyrazo- Iona-To a solution of 88 g. of l phenyl-3-amino-5-pyrazolone in 400 ml. of diethyl oxalate at 90 C. was added with stirring g. of m-chlorosulfonylbenzoyl chloride. The mixture was heated for /2 hour, cooled to 20 C. and the solid which separated was collected, triturated in water, ethyl acetate and dried, yielding 98 g. of product, M.P. 176177 C.

21 COUPLER XXX, INTERMEDIATE B I-phenyl-3-(3-sulf0benzamid0)5-pyraz0lone.A mixture of 58 g. of Intermediate A above in 250 ml. of 10% sodium hydroxide was stirred at room temperature for 2 hours after which time the solution was acidified with concentrated hydrochloric acid whereupon a solid separated. This solid was collected, washed with water and dried, yielding 23 g. of product, M.P. dec. 292 C.

Couplers XXXI and XXXII were each prepared according to the procedure given for coupler XXX above using the appropriate intermediates.

COUPLER XXXIII 1 -phenyl-3'(3,5-disulfobenzamido)-4-(4-hydr0xy-2-pentadecylphenylazo)-5-pyraz0l0ne dipotassium salt To a solution of 5 g. of l-phenyl-3-(3,5-disulfobenzamido) dipotassium salt (prepared according to the procedure given for Intermediate B, coupler XXX above using the appropriate intermediates) in 20 ml. of 50% pyridine was added at 20 C. a diazonium solution consisting of 3 g. of 4-amino-3-pentadecylphenol, 1.5 g. of isoamylnitrite and 2 g. of concentrated hydrochloric acid in 20 ml. of n-propyl alcohol. The resultant mixture was stirred at room temperature for 12 hours after which time it was poured into 100 ml. of saturated potassium chloride solution. The solid which separated was collected, and recrystallized from 50 ml. of 60% ethyl alcohol, yielding the product.

Couplers XXXIV, XXXV, XXXVI, XXXVII, and XXXVIII Were each prepared according to the procedure given for coupler XXXIII above using the appropriate intermediates.

COUPLER XXXIX [4- (3,5-dicarbxybenzamid0) phenyl] -3-ethoxy-4- 3- ctadecylcarbamylphenylthio) --pyraz0lone A mixture of 7.8 g. of Intermediate H below, 25 ml. of ethyl alcohol, ml. of 2 N aqueous NaOH, and 35 ml. of water was stirred at 85 C. for 15 minutes. The solution was cooled to room temperature and acidified with 1:2 concentrated HCl-water.

The solid which separated was filtered off, washed with water, acetonitrile, and recrystallized from methanol, yielding 4 g. of product, M.P. 200202 C.

COUPLER XXXIX, INTERMEDIATE A (4-nitrophenyl) -3-eth0xy-5-py'raz0l0ne .A mixture of 31 g. of 4-nitrophenylhydrazine, 100 ml. of ethyl alcohol, and 38 g. of ethyl-B,B-diethoxyacrylate was refiuxed for /2 hour. A solution of sodium ethoxide (prepared from 4.6 g. of sodium and 100 ml. of ethyl alcohol) was added and refluxed for another minutes. This solution was acidified with glacial acetic acid and the solid which separated was filtered off, and recrystallized from 250 ml. of n-butyl alcohol, yielding 31 g. of product, M.P. 153-4 C.

COUPLER XXXIX, INTERMEDIATE B 1- (4-amz'n0phenyl)-3-ellzoxy-5-pyrazolonc.A mixture of 15 g. of Intermediate A above in 150 ml. of ethyl alcohol was reduced using Pd/ charcoal at 50 p.s.i., hydrogen pressure.

The catalyst was filtered off and the solution poured into 500 ml. of water.

The product was filtered OE and air dried, yielding 8.2 g. of product, M.P. 121122 C.

COUPLER XXXIX, INTERMEDIATE C TrietIzyltrimcsate.-A mixture of '37 g. of trimesic acid (proc. N. Dak. Acad. Sc.; 8, 54 (1954); CA. (1955) 8898b), 100 ml. of ethyl alcohol, 50 ml. of benzene, and 1 ml. of concentrated H 80 was refluxed through a 6" packed column surmounted by a Dean-Stark water spouter for 24 hours after which time the residue was cooled and the solid which crystallized was filtered and dried.

The yield of the triester was 38 g., M.P. 1335 C.

22 COUPLER XXXIX, INTERMEDIATE D Diethyl ester of trimesic acid (3,5-dicarbethoxybenzoic acid).-To a solution of 147 g. of the Intermediate C above in 2 liters of ethyl alcohol was added with stirring 250 ml. of 2 N NaOH in 500 ml. of ethyl alcohol. This mixture was refluxed for 30 minutes and stirred at room temperature for 12 hours, during which time a solid separated. This solid was filtered off and recrystallized from a mixture of 500 ml. of ethyl alcohol and 500 ml. of water, yielding g. of product, M.P. 1535 C.

COUPLER XXXIX, INTERMEDIATE E 3,5-dicarbethoxybenzoyl chl0ride.-A mixture of 300 g. of Intermediate D above and 2 liters of thionyl chloride was refluxed for 2 hours, after which time it was concentrated in vacuo.

To the residue was added 250 ml. of dry benzene and again concentrated in vacuo.

The acid chloride thus formed was used as such in preparing Intermediate F below.

COUPLER XXXIX, INTERMEDIATE F 1 [4- (3,5 -dicarbeth0xybenzamido)phenyl -3-eth0xy-5- pyraz0l0ne.-A mixture of 6.6 g. of Intermediate B above and 8.5 g. of Intermediate E above and ml. of dry acetonitrile was refluxed for 5 hours. The mixture was cooled to room temperature and the solid was filtered off, dried, and recrystallized from glacial acetic acid, yielding 10 g. of product, M.P. 200-201 C.

COUPLER XXXIX, INTERMEDIATE G 3-octadecyIcarbamyiphenylsulfenyl chl0ride.Into a suspension of 8 g. of 3,3-dioctadecylcarbamyldiphenyldisulfide (Loria et al. US. patent application Ser. No. 154,- 841, filed Nov. 24, 1961) in ml. of anhydrous carbon tetrachloride was bubbled dry chlorine gas for 1 /2 hours at room temperature, during which time all of the solid dissolved and a clear light yellow solution was formed. The solution was concentrated in vacuo to a volume of 50 ml. to remove excess chlorine.

This solution of the sulfenyl chloride was used as such in the following reaction (i.e., Intermediate H below).

COUPLER XXXIX, INTERMEDIATE H 1 [4 (3,5-dicarbethoxybenzamido)phenyl]-3-eth0xy- 4 (3 octadecylcarbamylphenylthio)-5-pyraz0l0ne.A mixture of Intermediate G above and 9.35 g. of Intermediate F above in 200 ml. of dry dioxane was stirred at room temperature for 2 hours, heated to reflux for 1 hour, and concentrated in vacuo.

The residue was recrystallized from ethyl alcohol, yielding 8.5 g. of product, M.P. 156-8 C.

COUPLER XL 1 -(4-sulf0phenyl -3 (4 -sulf0anilin0) -4- (3-0ciadecylcarbaniylphenylthio) -5-pyraz0l0ne disodium salt A suspension of 25 g. of Intermediate B below in 100 ml. of ethyl alcohol and 200 ml. of 2% aqueous NaOH was stirred at room temperature for /2 hour, during which time all solid dissolved. The solution was cooled and acidified with 5 ml. of acetic acid and concentrated in vacuo.

The crude solid residue was recrystallized from methyl alcohol, yield 10 g. of product, M.P. 250 C.

COUPLER XL, INTERMEDIATE A 1-(4-flu0sulfonylphenyl)-3-(4 fluosulfonylanilino) 5- pyraz0l0ne.To 450 ml. of fiuosulfonic acid at 5 C. was added with stirring 80 g. of 1-phenyl-3-anilino-5- pyrazolone.

The resultant solution was stirred at 50 C. for 4 /2 hours, then poured onto 2 kg. of crushed ice. The solid was collected, washed with water, filtered, and dissolved in 2 liters of ethyl acetate. This solution was washed with 5% sodium bicarbonate solution, water, and saturated brine.

It was concentrated in vacuo and the residue was recrystallized from acetonitrile, yielding 36 g. of product, M.P. 290 C. decomp.

COUPLER XL, INTERMEDIATE B 1 (4 -fluosulfonylplzenyl)-3-(4-flu0sulfonylanilin0)-4 (3-octadecylcarbamylphenylthio)-5-pyraz0lone.A mixture of Intermediate G of Coupler XXXIX above (prepared from 24.5 g. of the disulfide) and 25 g. of Intermediate A above in 320 ml. of dry carbon tetrachloride was stirred at 55 C. for 12 hours.

The solution was then concentrated in vacuo and the residue was recrystallized from 300 ml. of ethyl acetate yielding 25 g. of product, M.P. 20911'C.

COUPLER XLI 4,4- (4-octadecyloxybenzylidene) bis [1-phenyl-3- (3,5- disulfobenzamido) 5-pyraz0l0ne] tetrapotassium salt To a refluxing solution of 5.2 g. of 1-phenyl-3-(3,5 disulfobenzamido)-5-pyrazolone dipotassium salt in 45 ml. of ethyl alcohol and 20 ml. of water was added a solution of 1.9 g. of Intermediate A below and 0.5 g. of piperidine in 35 ml. of ethyl alcohol. The solution was refluxed for /2 hour and cooled to room temperature. The solid which separated was collected, recrystallized from 90% ethyl alcohol, yielding 5 g. of product.

COUPLER XLI, INTERMEDIATE A 4-0ctadecyl0xybenzaldehyde.To a solution of 23 g. of sodium metal and 122 g. of 4-hydroxybenzaldehyde in 500 ml. of ethyl alcohol was added 333 g. of l-bromooctadecane. The mixture was refluxed with stirring for 20 hours during which time a solid separated. This solid was filtered and the filtrate was concentrated in vacuo. The residual material was then distilled at 253 C. at 1 mm. pressure, yielding 250 g. of product.

COUPLER XLII a-Benzoy l-OL- (4 -hydrxy-2-pentadecy lphenylazo) -4- (3 sulfobenzamido) acetanilide sodium salt To a solution of 4.5 g. of a-benzoyl-4-(3-chlorosulfonylbenzamido) acetanilide in 12 ml. of 90% pyridine was added at 20 C. a diazonium mixture consisting of 3.2 g. of 4-amino-3-pentadecylphenol, 1.4 g. of isoamylnitrite and 2 ml. of cone. hydrochloric acid in 20 ml. of n-propyl alcohol. The resultant solution was stirred at room temperature for 12 hours after which time it was poured into 50 ml. of saturated sodium chloride solution. The yellow solid which separated was collected, and recrystallized twice from ethyl alcohol, yielding 2.2 g. of product.

Coupler XLIII was prepared according to the procedure given for Coupler XLII above using the appropriate intermediates.

COUPLER XLV OL-BellZOyl-LZ- (3 -0ctadecy lcarbamy lphenyl thio -3 ,5 dicarboxyacetanilide hydroxide was heated at 40 C. for 1 hour after which 6 time it was acidified with concentrated hydrochloric acid. The solid which separated was collected and recrystallized twice from ethyl alcohol, yielding 2 g. of product, M.P. l40l42 C.

COUPLER XLV, INTERMEDIATE A a-Benzoyl-3,5-dicarbometh0xyacetanilide.To a refluxing mixture of 102 g. of ethyl a-benzoylacetate and g. of

sodium acetate in 100 ml. of xylene was added 105 g. of dimethyl 5-aminoisophthalate. The resulting solution was refluxed under a steam condenser for 3 hours after which time it was concentrated to /z the original volume and cooled to room temperature. The solid which separated was collected and recrystallized from methyl alcohol, yielding 40 g. of product, M.P. 167 C.

Coupler XLVI was prepared according to the preparation given for similar couplers in copending application U.S. Serial No. 25,295, filed April 28, 1960, now abandoned.

When the couplers given above were incorporated into silver halide emulsions which were developed in contact with a mordanted reception layer using an alkaline color developing composition containing the developing agent 4-amino-N-ethyl-N-(fl-hydroxyethyl)-aniline, the following colors of dye images were obtained on the reception layer from the respective couplers:

Coupler:

I Yellow H Do. III Do. 1V Orange-yellow. V Yellow. VI Do. VII Do. VIII Do. 1X Do. X Do. XI Cyan. XII Do. XIII Do, XIV Do. XV Do. XVI D0, XVII Do. XVIII Do. XIX Do. XX Do. XXI Do. XXII Do. XXIII Do. XXIV Do. XXV Do. XXVI Do. XXVH Do. XXVIII Do. XXIX Do. X)Q( Magenta. XXXI Do. XXXII Do. XXXIII Do. XXXIV Do. XXXV Do. XXXVI Do. XXXVII Do. XXXVIII Do. XXXIX Do. XL Do. XLI Do. XLII Yellow. XLIII Do. XLIV Do. XLV Do. XLVI Do.

When couplers having the formula DYELINK (COUPBALL) as described above are reacted with oxidized color developing agent, the connecting radical (LINK) is split and a diffusible preformed dye (DYE) is released which diffuses imagewise to a reception layer. An acidic solubilizing group on the preformed dye lends diifusibility to the dye molecule. The coupling portion of the coupler (COUP) couples with the color developing agent oxidation product to form a dye that is nonditfusible because of the attached ballasting group (BALL) in a noncoupling position. In this type of coupler, the color of the diffusible dye is determined by the color of the preformed dye moiety (DYE), the color of the reaction product of color developer oxidation product and the coupler moiety (COUP) being unimportant to the color of the diifusible image.

When couplers having the formula BALLLINK- (COUP---SOL) as described above are reacted with oxidized color developing agent, the connecting radical (LINK) is split and a diflusible dye is formed with the color developing agent oxidation product and the coupling portion (COUP) of the coupler which diffuses imagewise to a reception layer. Diffusibility is imparted to the dye by an acidic solubilizing group attached to a noncoupling position of the coupling portion (COUP) of the coupler or to the color developing agent. The ballast portion of the coupler remains immobile. In this type of coupler, the color of the diffusible dye is determined by the color of the reaction product of color developer oxidation product and the coupler moiety (COUP).

In using both types of couplers in the invention, the production of diffusible dye images is a function of the reduction of developable silver halide images which may involve direct or reversal development of the silver halide emulsions with an aromatic primary amino developing agent.

The light sensitive portions of the present photographic elements are photographic silver halide emulsions including silver chloride, silver bromide, silver bromoiodide, silver chlorobromide and silver chlorobromoiodide emulsions. Both conventional negative silver halide emulsions and direct positive emulsions can be utilized in our invention. Suitable direct positive emulsions include internal image silver halide emulsions and solarizing silver halide emulsions. Such emulsions are well known to those skilled in the art. Others are disclosed in U.S. Patent 2,184,013.

The internal image silver halide emulsions used in our invention are direct positive emulsions that form latent images predominantly inside the silver halide grains, as distinguished from silver halide grains that form latent images predominantly on the surface thereof. Such internal image emulsions were described by Davey et al. in U.S. Patent 2,592,250 issued April 8, 1952, and elsewhere in the literature. Internal image silver halide emulsions can be defined in terms of the increased maximum density obtained when developed with internaltype developers over that obtained when developed with surface-type developers. Suitable internal image emulsions are those which, when measured according to normal photographic techniques by coating a test portion of the silver halide emulsion on a transparent support, exposing to a light intensity scale having a fixed time between 0.01 and 1 second, and developing for 3 minutes at 20 C. in Developer A below (internal-type developer), have a maximum density at least five times the maximum density obtained when an equally exposed silver halide emulsion is developed for 4 minutes at 20 C. in Developer B described below (surface-type developer).

DEVELOPER A Hydroquinone 15 Monomethyl-p-aminophenol sulfate 15 Sodium sulfite (desiccated) 50 Potassium bromide Sodium hydroxide 25 Sodium thiosulfate 20 Water to make one liter.

DEVELOPER B P-hydroxyphenylglycine 10 Sodium carbonate 100 Water to make one liter.

The solarizing direct positive silver halide emulsions used in our invention are well-known silver halide emulsions which have been effectively fogged either chemically or by radiation to a point which corresponds approximately to the maximum density of the reversal curve as shown by Mees, The Theory of the Photographic Process, published by the Macmillan Co., New York, New York, 1942, pages 261-297. Typical methods for the preparation of solarizing emulsions are shown by Groves British Patent 443,245, February 25, 1936, who subjected emulsions to Roentgen rays until an emulsion layer formed therefrom, when developed without preliminary exposure, is blackened up to the apex of its graduation curve; Szaz British Patent 462,730, March 15, 1937, the use of either light or chemicals such as silver nitrate, organic sulfur compounds and dyes to convert ordinary silver halide emulsions to solarizing direct positive emulsions; and Arens U.S. Patent 2,005,837, June 25, 1935, the use of silver nitrate and other compounds in conjunction with heat to effect solarization. Kendall and Hill U.S. Patent 2,541,472, February 13, 1951, shows useful solarized emulsions particularly suspectible to exposure with long wavelength light and initial development to produce the Herschel effect described by Mees above, produced by adding benzothiazoles and other compounds to the emulsions which are fogged either chemically or with white light. In using the emulsions a suflicient reversal image exposure is employed using minus blue light of from about 500-700 m wavelength, preferably 520 554 m to substantially destroy the latent image in the silver halide grains in the region of the image exposure.

The subject photographic emulsions used in producing colored images in accordance with the invention can contain the addenda generally utilized in such products including optical sensitizers, speed-increasing materials, antifoggants, coating aids, gelatin hardeners, plasticizers, ultraviolet absorbers and the like.

In the preparation of silver halide dispersions employed for preparing the present photographic emulsions, there can be employed as the dispersing agent or substrate for the silver halide in its preparation, gelatin or some other colloidal material such as colloidal albumin, a cellulose derivative, or a synthetic resin, for instance, a polyvinyl compound, although gelatin is preferred. Such colloidal materials can also be used in the non-light-sensitive layers in the subject elements in accordance with usual practice. Such hydrophilic colloids are well known.

The above-described emulsions of the invention can be coated on a wide variety of photographic emulsion supports. Typical supports include cellulose nitrate film, cellulose acetate film, polyvinyl acetal film, polystyrene film, polyethylene terephthalate film, polyethylene film, polypropylene film, and related films of resinous mate rials, as well as paper, glass, and others.

In preparing the photographic elements of the invention, silver halide emulsions are preferably coated on photographic supports in the form of multilayer color photographic elements wherein at least three emulsion layers sensitive to different regions of the visible spectrum are coated on the support. For example, the uppermost lightsensitive emulsion layer is generally selectively sensitive to blue light, the next light-sensitive emulsion layer is generally selectively sensitive to green light, and the light-sensitive emulsion layer nearest the support is generally selectively sensitive to red light. Between the blue and green sensitive emulsion layers there is typically disposed a Carey Lea filter layer for absorbing blue radiation that may be transmitted through the uppermost blue sensitive layer. The red, green and blue light-sensitive silver halide layers have contiguous to the silver halide (e.g., incorporated in the emulsion or in adjacent layers) a cyan-forming, a magenta-forming and a yellow-forming coupler respectively. However, the physical disposition of the red, green and blue light-sensitive silver halide layers within the present photographic elements can be widely varied in accordance with usual practice. Such multilayer photographic elements can also have other inter- 27 layers or sublayers for specialized purposes in accordance with usual practice.

In another embodiment of the invention, a single layer light-sensitive element could be utilized to prepare diffusion transfer full color images. Three types of packets of dilferently sensitized silver halide emulsions and their corresponding couplers for subtractive color photography can be incorporated into a single emulsion layer on a photographic support. Reference is made to Godowsky U.S. Patent 2,698,794 for suitable methods for preparing silver halide-color coupler packets.

The reception layer used to receive the diffused dye images on color development of the photoelements of the invention can be either a separate sheet pressed in contact with the photoelement or a layer integral with the photoelement.

When the reception layer is a separate reception sheet, the development and transfer operations can be effected by bathing either or both the exposed emulsion layer and the mordanted reception sheet in the developing solution before rolling into contact with each other, Alternately, a viscous developing composition can be placed between the elements for spreading in a predetermined amount across and in contact with the exposed surface of the sensitive element so as to provide all of the solution required for the picture area. The viscous developing composition is desirably utilized in one or more pods integral with the photoelement or the reception sheet that can be readily ruptured when development is desired, suitable viscous developer utilization techniques being disclosed in Land U.S. Patents 2,559,643, 2,647,049, 2,661,293, 2,698,244, 2,698,798 and 2,774,668.

When the reception layer for receiving the difiusible dye is an integral part of the photosensitive assembly, it is also useful. A typical element of this type can compn'se a support, a mordanted colloid layer thereon and the various emulsion layers described above coated thereover. When easily dissolved emulsions are used such as those containing polyvinyl alcohol or alkali-soluble cellulose etherphthalate vehicles, or a wet or dry stripping layer containing such vehicles is provided between the emulsions and reception layer, the developed emulsion layers can then be separated from the reception layer leaving the dye image thereon. Similarly, the reception layer can be initially bonded to the outer emulsion surface. In this case, it is preferred to expose through the support of the sensitive element unless the reception layer itself is transparent. Such photoelements can be processed in the same manner as those not containing integral reception layers.

The reception layers in the photoelements of the invention can contain any of the conventional mordant materials for acid dyes. The reception layer can contain mordants such as polymers of amino guanidine derivatives of vinyl methyl ketone such is described in the Minsk U.S. Patent 2,882,156 granted April 14, 1959. Other mordants include the 2-viny1 pyridine polymer metho-ptoluene sulfonate and similar compounds described in Sprague et al. U.S. Patent 2,484,430 granted October 11, 1949, and cetyl trimethylammonium bromide, etc. Particularly effective mordanting compositions are described in copending applications of Knechel et al. U.S. Serial No. 211,095 filed July 19, 1962, and Bush U.S. Serial No. 211,094 filed July 19, 1962. The mordanting compositions described in the Knechel et al. application comprise at least one hydrophilic organic colloid containing a finely-divided, uniform dispersion of droplets or globules of a high-boiling, water-immiscible organic solvent in which is dissolved a high concentration of a cationic, nonpolymeric, organic dye-mordanting compound for acid dyes. The mordanting compositions described in the Bush application comprise at least one hydrophilic organic colloid containing a finely-divided, uniform dispersion of particles of a salt of an organic acidic composition containing free acid moieties and a cationic, nonpolymeric,

organic dye-mordanting compound for acid dyes. Useful cationic or basic organic dye-mordanting compounds for acid dyes include quaternary ammonium and phosphonium, and ternary sulfonium compounds in which there is linked to the N, P, or S onium atom at least one hydrophobic ballast group such as long-chain alkyl or substituted alkyl groups. Furthermore, the reception layer or sheet can be sufficient by itself to mordant the dye as in the case of use of a sheet or layer of a polyamide or related polymeric material.

Reception sheets for the dye images, as well as the photoelements of the invention can contain ultraviolet absorbing materials. In the reception sheets, ultraviolet absorbers protect the mordanted dye images from fading and print-out due to ultraviolet light. In the photoelements, ultraviolet absorbers can serve as taking filters to reduce ultraviolet sensitivity- Typical ultraviolet absorbing materials are described in copending applications of Sawdey, U.S. Serial Nos. 144,228 filed October 10, 1961, and 183,417 filed March 29, 1962. Illustrative useful ultraviolet absorbing materials disclosed by Sawdey have the formulas wherein: R is a phenyl radical including such substituents as hydrogen atoms, halogen atoms, alkyl radicals, alkoxy radicals or hydroxy radicals; and R R and R are hydrogen atoms, halogen atoms, nitro radicals, alkyl radicals, alkoxy radicals, aryl radicals or aryloxy radicals.

As referred to hereinabove, photographic elements of the invention prepared with conventional developing-out emulsions can be used to prepare either negative or positive color reproductions. In preparing negative color reproductions only a single development with a color developer is needed. However, in preparing positive color reproductions with such emulsions, two developments are needed. An initial development is used to develop the silver halide in the areas of exposure to form a negative silver image. The remaining unexposed and undeveloped silver halide (positive image areas) is rendered developable 'by flash exposing to white light or by chemical fogging with reducing agents such as alkali metal borohydrides in the usual manner, and thereafter color developed to form ditfusible dyes as described above. Preferably, the initial negative development is effected with a black-and-white development with a developing agent that does not modify or couple with the color coupiers in the areas of development so that no ditfusible dyes are liberated. Typical black-and-white developing agents are hydroquinone, N-methyl-p-aminophenol sulfate Elon), and 3-pyrazolidones such as 1-phenyl-3-pyrazolidone, 4-methyl-l-phenyl-3-pyrazolidone, 1-phenyl-4,4- dimethyl-3-pyrazolidone and other 4,4-dialkyl-3-pyrazolidones of the type disclosed by James et al. in U.S. Patents 2,688,549 granted September 7, 1954, and 2,751,300 granted June 19, 1956.

Also the initial negative development of photographic elements of the invention prepared with conventional developing-out emulsions in a positive process can be effected with the aromatic primary amino color developing agents described above. 'However, with such color developing agents, diffusible dyes are produced in the areas of exposure (negative image area) on development that must be removed by washing out, diffusion into a processing container or tank, by transfer to a receiving sheet or by other means prior to rendering the remaining undeveloped and unexposed silver halide developable and the second or color development effected.

The developing agents used in the present process can be incorporated in the photographic elements. Sulfur dioxide complexes of hydroquinone and N-methyl-paminophenol sulfate are particularly useful incorporated black-and-white developers- Also, Schiff base derivatives of aromatic primary amino color developing agents such as that formed by reacting o-sulfobenzaldehyde and N,N-diethyl-3-methyl-4-aminoaniline can be utilized. Such incorporated developing agents can be activated by immersing the photographic element in an aqueous alkaline solution or by spreading an aqueous alkaline solution on the surface of the element. Such incorporated developing agents can be positioned in any layer of the present photographic elements from which the developing agents can be readily made available for development on activation with aqueous alkaline solutions. Generally such incorporated developing agents are either incorporated in the light-sensitive silver halide emulsion layers or in layers contiguous thereto.

In another embodiment of the invention for preparing direct positives with photographic elements containing conventional silver halide emulsions, the color developer can be incorporated in the photographic element (e.g., as a Schifi base of the color developing agent as described above) and the black-and-white development effected under acidic conditions (e.g., pH 0.9) with an aqueous solution of a reducing agent such as titanous chloride (e.g., 1% aqueous solution) which is a mild reducing agent under such acidic conditions. After the negative silver image is developed, the processing solution is made alkaline. Under alkaline conditions the titanous chloride is a stronger reducing agent and serves as a chemical fogging agent for remaining unexposed and undeveloped silver halide to form a positive image area. In the alkaline medium the Schilf base of the color developer splits and color development takes place liberating diffusible dyes in the chemically fogged area that migrate to a mordanted reception layer to form positive images.

The drawing illustrates in section and in elevation typical photographic elements of the invention.

FIG. 1 of the drawing illustrates a light sensitive element that can be utilized to prepare color diffusion transfer images in conjunction with a separate mordanted receiving sheet. On photographic support is red sensitive emulsion layer 11 that contains a nondiffusible coupler of the invention that forms a diffusible cyan dye on color development. Over red sensitive emulsion layer is interlayer 12 that serves to separate green sensitive layer emulsion 13 and red sensitive layer 11. Interlayer 12 can contain such addenda as antioxidants, couplers to react to form nondiffusible dyes with oxidized color developing agent from adjacent layers, filter dyes such as a magenta filter dye and the like. Green sensitive emulsion layer 13 contains a nondiffusible coupler of the invention that forms a diffusible magenta dye on color development. Over green sensitive emulsion layer 13 is interlayer 14 that serves to separate green sensitive emulsion layer 13 and blue sensitive emulsion layer 15. Interlayer 14, like interlayer 12, can contain antioxidants, couplers that react to form nondiffusible dyes with oxidized color developing agent from adjacent layers, filter dyes and the like. Interlayer 14 typically contains yellow Carey Lea silver to serve as a filter. Blue sensitive emulsion layer 15 contains a nondiffusible coupler of the invention that forms a difiusible yellow dye on color development. Over blue sensitive emulsion layer 15 is topcoat protective layer 16 that typically contains such addenda as antioxidants and ultraviolet absorbers. Emulsion layers 11, 13 and 15 are silver halide emulsion layers and can be either conventional negative-type developing out emulsions or direct positive emulsions as described above. On color development, the resulting diffusible dyes diffuse imagewise in register to a receiving sheet containing a mordant for acid dyes superposed on topcoat protective layer 16.

FIG. 2 of the drawing illustrates a light sensitive element that can be utilized to prepare color images in ac cordance with the invention that has integral therewith a mordanted reception layer. Layers 23 to 28 of FIG. 2 correspond to layers 11 to 16 of FIG. 1 described above respectively. On support 20 is mordanted reception layer 21 containing a mordant for acid dyes. Over mordanted reception layer 21 is stripping layer 22 that serves to separate mordanted reception layer 21 from the light sensitive and coupler-containing layers. On color development, the resulting diffusible dyes diffuse imagewise in register to mordanted reception layer 21. Thereafter stripping layer 22, along with layers 23 to 28, can be readily removed leaving -a color image on supported mordanted reception layer 21.

The photographic elements set out in the drawing are merely illustrative of typical embodiments of the invention. As described above, other layers than those illustrated can be utilized. For example, the color couplers can be suitably employed in layers adjacent to the light sensitive layers instead of in the light sensitive layers. Also, the selectively sensitized silver halide emulsion layers can be disposed in different orders than that shown in the drawing. In addition, layers serving as masking layers can be utilized. For example, a magenta colored masking image formed in a layer over the red-sensitive cyan-forming layer can be utilized. In such an embodiment, a direct positive red-sensitive emulsion containing a mangenta-forming coupler can be coated over a negative-type red-sensitive emulsion containing a cyan-forming coupler, the blue and the green-sensitive emulsions also being negative-type emulsions. Such magenta masks are of use in photographic elements used for making internegatives in photocopy work, for example.

The following examples illustrate preferred embodiments of our invention. The coupler numbers referred to in the examples are those set out and described hereinabove.

Example 1 A color film having the structure substantially as shown in FIGURE 1 was prepared by coating a subbed cellulose acetate film support successively with the following layers:

(1) Red-sensitive layer (e.g., layer No. 11, FIG. 1). A 5% solution (0.0054 mole) prepared by dissolving 4.2 g. of cyanforming coupler XX in 4 ml. of dimethylformamide and 43 ml. of trimethylamine, made up to a total weight of 86.5 g. with water, was added to 200 g. of a 3% gelatin solution and the solution was adjusted to a pH of 6.3 with 20% citric acid solution. The resultant gelatin solution was added to a portion of a redsensitized /20 silver chlorobromide-gelatin emulsion containing 0.06 mole of silver halide. This resulting emulsion was then coated on the support to give mg. of the coupler and mg. of silver per sq. ft.

(2) Interlayer (e.g., layer N0. 12, FIG. 1).A solution of 75 g. of the antioxidant 2-octadecyl-4-sulfohydroquinone potassium salt in 5000 ml. of water was added to 4540 g. of a 10% photographic gelatin solution. This solution was coated on the bottom layer to give 15 mg. of the antioxidant per sq. ft.

(3) Green-sensitive layer (e.g., layer N0. 13, FIG. 1).A 5% solution (0.0057 mole) of magenta-forming coupler XXX, prepared and adjusted in the same manner as in No. 1 above, was added to a portion of a greensensitized 80/20 silver chlorobromide-gelatin emulsion containing 0.06 mole of silver halide. The resulting emulsion was then coated to give 100 mg. of the coupler and 150 mg. of silver per sq. ft.

(4) Interlayer (e.g., layer N0. 14, FIG. 1).The solution of antioxidant prepared as described in No. 2 above was coated to give 15 mg. of the antioxidant per sq. ft.

(5) Blue-sensitive layer (e.g., layer N0. 15, FIG. 1).- A 5% solution (0.005 mole) of yellow-forming coupler I, prepared and adjusted in the same manner as described in No. 1 above, was added to a portion of a blue-sensitive 2/98 silver chlorobromide-gelatin emulsion contain- 31 ing 0.06 mole of silver halide. This emulsion melt was then coated to give 100 mg. of the coupler and 150 mg. of silver per sq. ft.

(6) Top coat layer (e.g., layer N0. 16, FIG. ]).The solution of antioxidant prepared as described in No. 2 above was coated to give 15 mg. of the antioxidant per sq. ft.

The film prepared as described was then exposed through a color negative, immersed in Color Developer C below together with a mordanted receiving sheet such as a gelatin-sized formaldehyde-hardened paper base with a gelatin layer containing thorium nitrate for 30 seconds. The two elements then squeegeed together for 7 minutes, stripped apart and the receiving element carrying the colored image rinsed in 1% acetic acid solution followed by cold water and then dried. A positive reproduction in full colors resulted. Negative developing-out silver halide emulsions were used.

COLOR DEVELOPER C Water to make one liter.

Example 2 A multilayer color film having a structure substantially as shown in FIGURE 1 was coated on a subbed cellulose acetate support with these emulsion layers prepared, in the manner as described in Example 1 above, as follows:

(1) Red-sensitive layer (e.g., layer N0. 11, FIG. 1). This layer contained a dispersion of cyan coupler XX (100 mg./ft. in a red-sensitized 80/20 silver chlorobromide emulsion (gelatin 200 mg./ft. and silver 60 mg./ft.

(2) Interlayer (e.g., layer N0. 12, FIG. 1).-This layer contained a dispersion of the antioxidant 2-octadecyl-4-sulfohydroquinone potassium salt (15 mg./ft. in gelatin (90 mg./ft.

(3) Green-sensitive layer (e.g., layer N0. 13, FIG. 1.)This layer contained a dispersion of coupler XXXVII (80 mg./ft. in a green-sensitized 80/20 silver chlorobromide emulsion (gelatin 100 mg./ft. and silver 30 mg./ft.

(4) Interlayer (e.g., layer No. I 4, FIG. 1).This layer was identical to No. 2 above.

(5) Blue-sensitive layer (e.g., layer N0. 15, FIG. I).- This layer contained a dispersion of coupler XLVI (180 mg./ft. in a blue-sensitive 2/98 silver chlorobromide emulsion (gelatin 150 mg./ft. and silver 100 mg./ft.

(6) Topcoat layer (e.g., layer N0. 16, FIG. 1). This layer was identical to No. 2 above.

The above film was exposed through a color negative transparency followed by treatment for 5 seconds in Color Developer D COLOR DEVELOPER D pH adjusted to 11.0-11.2.

Then the film was squeegeed into contact with a receiving sheet as described in Example 1 that had been treated for 25 seconds in the same color developer. The resulting sandwich was then maintained at 70 F. for 2 /2 minutes and then separated to give a multicolor positive print on the receiving sheet corresponding to the original color negative. Negative developing-out silver halide emulsions were used.

Example 3 i The film prepared as described in Example 2 above was exposed through a positive color transparency and then developed at 70 F. for 3 minutes in Black-and- White Developer E.

BLACK-AND-WHITE DEVELOPER E G. N-p-methylaminophenolsulfate 3 Sodium sulfite des 45 Sodium carbonate monohydrate 68 Hydroquinone 12 Potassium bromide 2 Water to make one liter.

The film was rinsed and the residual unexposed and undeveloped silver halide (i.e., positive image) was exposed by flashing to white light. It was then color developed in contact with a mordanted receiving sheet in the same manner as described in Example 2 above. A positive color reproduction of the original positive transparency was thus obtained.

Example 4 A multilayer color film similar to the one described in Example 2 above except that an Elon-hydroquinone-SO; complex was incorporated in each of the light-sensitive layers as described below:

(1) Red-sensitive layer.As in Example 2 above plus 90 mg./ft. of the Elon-hydroquinone-SO complex.

(2) InZerlayer.-As in Example 2 above.

(3) Green-sensitive layer.As in Example 2 above plus 40 mg./ft. of the Elon-hydroquinone-SO complex.

(4) Interlayer.As in Example 2 above.

(5) Blue-sensitive layer.--As in Example 2 above plus 133 mg./ft. of the Elon-hydroquinone-SO complex.

(6) Topcoat layer.As in Example 2 above.

The above film was exposed through a positive color transparency and then dipped into the following activator solution:

G. Sodium carbonate 20 Ascorbic acid 1 Water to make 1 liter. pH adjusted to 12 with NaOH.

After 45 seconds at about 70 F., the film was white light flashed and rolled into contact with a mordanted receiving sheet as described in Example 1 which had been previously saturated with the color developer described in Example 2 above. After 7 minutes at F., the film and residue were separated and the resulting positive color reproduction on the receiving sheet was rinsed in 1% acetic acid solution. The above process was also carried out by dipping the film following the intial image exposure directly into the color developing solution and after one minute squeegeeing into contact with the mordanted receiving sheet wet with the color developing solution. While the film was immersed in the color developing solution, negative development was allowed to proceed. The black-and-white developing agent diffused out of the film and into the color developing solution and was replaced by the color developer. Upon reversal exposure, the diffusible dye images were formed in the respective emulsions and diffused imagewise to the reception layer. The Elon-hydroquinone-SO complex was prepared as follows:

Elan-S0 c0mplex.A 172.2 g. portion of monomethylp-aminophenol sulfate was added to a solution of 40 g. sodium hydroxide and 25 g. of sodium sulfite in 500 cc. of water. The resulting free base was extracted in a separatory funnel using 200 cc. of isopropyl alcohol. Sulfur dioxide was then bubbled into the solution until the white precipitate which initially formed was dissolved and a 33 deep orange solution obtained. A white crystalline product was obtained by chilling the solution with a solid carbon dioxide-acetone bath, and filtering off and drying the resulting crystals.

Hydroquz'none-SO cmplex.-A 110 g. portion of hydroquinone in 700 cc. of water at 40 C. was saturated with sulfur dioxide and cooled to C. The resulting yellow product which crystallized out was filtered off and dried. The Elon-hydroquinone-sulfur dioxide complex was then prepared for use in the emulsions by dissolving l g. of the Elon-SO complex and 15 g. of the hydroquinone-SO complex above in 50 cc. of ethyl alcohol containing cc. of water.

Example 5 Multilayer photographic elements suitable for use in preparing three-color difiusion transfer images of the type illustrated by FIG. 1 were prepared by coating on cellulose acetate film supports the following layers numbered in sequence from the support:

(1) An emulsion optically sensitized to red light containing silver bromoiodide at a coverage of 135 mg. of silver per square foot, gelatin at a coverage of 250 mg. per square foot, cyan-forming coupler )Q( at a coverage of 55 mg. per square foot, and 2,5-dihydroxy-4-octadecyl-benzene sulfonic acid potassium salt at a coverage of 4.5 mg. per square foot;

(2) Gelatin at a coverage of 100 mg. per square foot, 1- hydroxy N- [5- 2,4-di-t-amylphenoxy) butyl] -2-naphthamide at a coverage of 45 mg. per square foot, and 1-hydroxy-4'- (4-t-butylphenoxy) -4-phenylaZo-2-naphthanilide at a coverage of mg. per square foot;

( 3) An emulsion optically sensitized to green light containing silver bromoiodide at a coverage of 80 mg. of silver per square foot, gelatin at a coverage of 113 mg. per square foot, magneta-forming coupler XXXVII at a coverage of 50 mg. per square foot, and 2,5-dihydroxy- 4-octadecyl-benzene sulfonic acid potassium salt in a coverage of 4.4 mg. per square foot;

(4) Gelatin at a coverage of 100 mg. per square foot, Carey Lea silver at a coverage of 15 mg. per square foot, and l-hydroxy-N-[5-(2,4-di-t-amylphenoxy)butyl]-2- naphthamide at a coverage of 45 mg. per square foot;

(5) An emulsion optically sensitized to blue light containing silver bromoiodide at a coverage of 100 mg. of silver per square foot, gelatin at a coverage of 100 mg. per square foot, yellow-forming coupler XLVI at a coverage of 100 mg. per square foot, and 2,5-dihydroxy-4 octadecyl-benzene sulfonic acid potassium salt at a coverage of 3.3 mg. per square foot; and

(6) A gelatin overcoat at a coverage of 50 mg. per square foot.

The silver bromoiodide utilized in layers 1, 3 and 5 was of the internal image type having high internal sensitivity and low surface sensitivity and prepared by the procedure described in Davey et al., US. Patent 2,592,250, issued April 8, 1952. Conventional couplers that form nondiffusible dyes on color development were utilized in layers 2 and 4 to prevent wandering of oxidized color developing agent between the light sensitive layers. The prepared photographic elements were then exposed for A second with a 500 watt positive lamp and a 4.08 Corning filter in an Eastman Type IB intensity scale sensitometer and developed in Color Developer F below.

COLOR DEVELOPER F Grams Piperidino hexose reductone 0.80 fi-nitrobenzimidazole 0.05 Sodium hydroxide 16.0 p-Aminoethyl-fi-hydroxyaniline 20.0

Water to make one liter.

The processing of the multilayer photographic elements was carried out by immersing for 20 seconds at 68 F. the elements and photographic image receiving sheets containing the cationic mordant, dimethyl-B-hydroxyethyl-a- (octadecylamido)-propyl ammonium dihydrogen phosphate, bringing the photographic elements and receiving sheets in intimate contact for 5 minutes, and then separating the photographic element and the receiving sheet to produce a positive full-color image on the receiving sheet. In the present instance, direct positives resulted as internal image silver halide emulsions were utilized in the light sensitive layers. The values of the color D (measured on a Kodak Model 31A Densitometer) on the receiving sheet are summarized by the data set out in Table I below. As can be observed from the data in Table I, transfer color images having high densities were obtained on the receiving sheets.

TABLE I.Dm=ix OF TRANSFERRED DYE Example 6 A color film having a structure substantially as shown in FIG. 1 was coated on a subbed cellulose acetate support with the following layers prepared in the manner described in Example 1 above as follows:

(1) Red-sensitive layer (e.g., layer No. 11, FIG. I).-- To one mole of a melted, internal image, direct positive emulsion of the type described in Example 5 that had been red-sensitized, was added 108 g. of cyan coupler XX in 2500 ml. of water and enough photographic gelatin to make a total of 139 g. per mole of silver halide. This solution was then coated so as to obtain 193 mg./ft. of gelatin, 150 mg./ft. of coupler, and 150 mg./ft. of silver.

(2) Interlayer (e.g., layer N0. 12, FIG. I).To 4540 g. of a 10% photographic gelatin solution was added 250 g. of the anti-oxidant, 2-octadecyl-4-sulfohydroquinone potassium salt, in 5000 m1. of hot water. This was coated to obtain 91 mg./ft. of gelatin and 50 -mg./ft. of the anti oxidant.

(3) Green-sensitive layer (e.g., layer N0. 13, FIG. I .-To one mole of a melted, internal image, direct positive emulsion of the type described in Example 5 that had been green-sensitized, was added 81 g. of magenta coupler XXXVII in 3000 ml. of water and enough photographic gelatin to have a total of 162 g. per mole of silver halide. This solution was coated so as to obtain 180 mg./ft. of gelatin, mg./ft. of coupler, and mg./ft. of silver.

(4) Interlayer (e.g., layer N0. 14, FIG. 1).To 4540 g. of 10% photographic gelatin solution was added 250 g. of the anti-oxidant used in layer 2 in 5000 ml. of hot water and 4.0 g. of yellow Carey Lea silver as a dispersion. This solution was then coated to obtain 91 mg./ft. of gelatin, 50 mg./ft. of antioxidant, and 8 mg./ft. of Carey Lea silver.

(5) Blue-sensitive layer (e.g., layer N0. 15, FIG. 1). To one mole of a melted, internal image, direct positive emulsion of the type described in Example 5 that was inherently blue light-sensitve, was added 144 g. of coupler XLVI that had been dissolved in 750 ml. of ethyl alcohol and 3000 ml. of water and enough photographic gelatin to have a total of 118 g. per mole of silver halide. This solution was coated so as toobtain 161 mg./ft. of gelatin, 200 mg./ft. of coupler, and mg/ft. of silver.

(6) T opcoat layer (e.g., layer N0. 16, FIG. 1).To 4540 g. of a 10% photographic gelatin solution was added 250 g. of ultraviolet absorbing compound, 5-(4-methoxy- 3-sulfo)benzylidene-2-phenylimino-3-octylthiazolidone sodium salt in 5000 ml. of water. to obtain 91 mg./ft. of gelatin-and 50 mg./ft. of the ultraviolet absorbing compound. The direct positive film prepared as described was exposed to a colored subject,

This solution was coated 35 then developed by applying a limited quantity of the following viscous developing composition, Color Developer G, between the emulsion surface and a mordanted reception sheet as the emulsion and sheet were rolled into contact with each other.

COLOR DEVELOPER G (The developer ingredients were dissolved in the water,

then the whole added to 700 g. of a 4% aqueous solution of alkali-soluble carboxymethylcellulose.)

The resulting sandwich was maintained at a temperature of 80 F. for about 5 minutes after which the emulsion was separated from the receiving sheet to obtain a direct positive image of the subject in full color on the receiving sheet. The mordanted reception sheet included a paper base on which was coated a gelatin solution of a mixture of the quaternary ammonium salt mordants, dimethyl-,8- hydroxyethyl-a-[octadecylamido1-propyl ammonium dihydrogen phosphate and distearyl dimethylammonium chloride, so as to obtain 75 mg. of each mordant and 100 mg. of gelatin per sq. ft. In the development process above each of the light-sensitive emulsion layers (e.g., layers 11, 13 and 15 of FIG. 1) developed in the positive (unexposed) region by virtue of the hydrazine compound of the developer neutralizing the charges on the image exposed silver halide grains and also nucleating (fogging) the unexposed grains so that they develop, with the result that the oxidized developing agent produced thereby caused each of the cyan, magenta and yellow dye-forming couplers to split at the coupling position and the coupler moieties thus released each to form a dififusible dye with the oxidized developer, and which dyes then ditfused imagewise in register to the reception sheet to form a multicolor positive image thereon. The photographic element of the invention described in this example can be modified to compensate for any undesirable eflfects the color couplers may have upon the silver halide emulsions, particularly during periods of storage, or to obviate the filter effect of the colored couplers. Any of the couplers can be incorporated in a colloid layer adjacent to the silver halide emulsion layers, thus the magenta coupler XXXVII' of layer 13 which is colored can be added to layer 12 rather than to emulsion layer 13 with the result that the speed of the green sensitive emulsion layer 13 is in effect increased. Thus, the intimate association of silver halide and coupler can take the form of the coupler being in the silver halide emulsion or a layer effectively adjacent thereto, or in mixed packet systems described hereinabove the coupler can be in packets containing silver halide dispersed in a matrix containing other packets of ditferently sensitized silver halide and color coupler. The antioxidants in the interlayers 12 and 14 serve to prevent undue wandering of the oxidized developing agent from layer to layer, and thus to prevent the production of more dye in an emulsion than wanted. If desired any one or all of the emulsion layers 11, 13 and '15 can contain an antioxidant such as that of layers 12 and 14.

Example 7 A color film having a structure substantially as shown in FIG. 1 was coated on a subbed cellulose acetate support with the following layers prepared in the manner described in Example 1 above as follows:

(1) Red-sensitive layer (e.g., layer No. 11, FIG. 1).- To one mole of a direct positive emulsion of the type described in Example 2 of Leermakers, US. Patent 2,184,013 that had been red-sensitized was added 81 g.

of coupler XX and enough photographic gelatin to have a total of 162 g. of gelatin per mole of silver halide. This solution was coated to obtain 200 mg./ft. of silver, 150 mg./ft. of coupler, and 300 mg./ft. of gelatin.

(2) Interlayer (e.g., layer N0. 12, FIG. 1).To 4540 g. of a 10% photographic gelatin solution was added g. of the antioxidant, 2-octadecyl-4-sulfohydroquinonc potassium salt, in 200 ml. of water and 150 g. of the magenta filter dye, 1-hydroxy-4-(p-tert.butylphenoxy)-4- phenylaZo-Z-naphthanilide. This solution was then coated to obtain 91 trig/ft. of gelatin, 15 mg/ft? of antioxidant and 30 mg./ft. of the filter dye.

(3) Green-sensitive layer (e.g., layer N0. 13, FIG. I).To one mole of a direct positive emulsion of the type described in Example 5 of Leermakers US. Patent 2,184,013 that had been green-sensitized was added 54 g. of coupler XXXI in 1500 ml. of water and enough photographic gelatin to have a total of 162 g. of gelatin per mole of silver halide. This solution was coated to obtain 200 rug/ft. of silver, 300 mg./ft. of gelatin, and mg./ft. of coupler.

(4) Interlayer (e.g., layer N0. 14, FIG. 1).To 4540 g. of a 10% photographic gelatin solution was added 75 g. of 2-octadecyl-4-sulfohydroquinone potassium salt in 5000 ml. of hot water and 4 g. of yellow Carey Lea silver as a dispersion. This solution was then coated to obtain 91 mg./ft. of gelatin, 15 mgjft. of antioxidant, and 8 rug/ft. of Carey Lea silver.

(5) Blue-sensitive layer (e.g., layer N0. 15, FIG. 1).- To one mole of a blue-sensitized solarizing emulsion of the type described in Example 1 of Kendall et al. US. Patent 2,541,472 was added 108 g. of coupler XLV in 1500 ml. of water and enough photographic gelatin to have a total of 162 g. of gelatin per mole of silver halide. This solution was coated to obtain 200 mg./ft. of silver, 300 mg./ ft. of gelatin, and 200 mg/ft. of coupler.

(6) Topcoat layer (e.g., layer N0. 16, FIG. 1).To 4540 g. of a 10% photographic gelatin solution was added 250 g. of ultraviolet absorbing compound, 5-(4-methoxy- 3 sulfo)benzylidene 2-phenylimino-3-octylthiazolidone sodium salt in 5000 ml. of water. This solution was coated so as to obtain 91 mg./ft. of gelatin and 50 mg./ft. of the ultraviolet absorbing compound. The above described color film was exposed to a colored subject then rolled into contact with mordanted reception sheet containing dimethyl fl-hydroxyethyl-a-(octadecylamido)propyl ammonium dihydrogen phosphate, with a limited quantity of Developer H between the film and the sheet:

DEVELOPER H Sodium sulfite (anhydrous) g 2 Potassium bromide 1 Sodium carbonate (anhydrous) g 40 4-amino-N-ethyl-N-(fi-hydroxyethyl)aniline g 10 Sodium hydroxide (10%) ml 26 I Water to make one liter.

After 3 minutes at 75 F. the film was peeled oll the reception sheet leaving a multicolored positive image of the subject on the reception sheet.

Example 8 Example 9 A color film having the structure substantially as shown .in FIG. 2 was prepared by coating a subbed white opaque 37 cellulose acetate film support successively with the following layers:

(1) Reception layer (e.g., layer N0. 21, FIG. 2).-The

cationic modrant, N-cetyl-N-ethylmorpholinium ethosulfate, was dispersed in a 10% photographic gelatin solution and coated to obtain 600 mg./ft. of gelatin and 200 mg./ft. of the mordant.

(2) Stripping layer (e.g., layer N0. 22, FIG. 2).-Alkalisoluble cellulose ether phthalate was coated at a coverage of 100 mg./ft.

(3) Red-senstive layer (e.g., layer N0. 23, FIG. 2).

Same as layer 1 of Example 6.

(4) Imerlayer (e.g., layer N0. 24, FIG. 2).Same as layer 2 of Example 6.

(5) Green-sensitive layer (e.g., layer No. 25, FIG. 2).

Same as layer 3 of Example 6.

(6) Interlayer (e.g., layer N0. 26, FIG. 2).Same as layer 4 of Example 6.

(7) Blue-sensitive layer (e.g., layer N0. 27, FIG. 2).

Same as layer 5 of Example 6.

(8) T opcoat layer (e.g., layer N0. 28, FIG. 2).fiSame as layer 6 of Example 6.

The prepared direct positive film with integral dye reception layer was then exposed to a colored subject and de-. veloped in Developer G. The development was carried out by bringing into contact a porous polycarbonate web saturated with the developer and the emulsion side of the exposed photographic element. The resulting sandwich was maintained at a temperature of about 72 F. for about 3 minutes. The web was then separated from the photographic element, the emulsion layers and interlayers being retained on the web and the stripping layer having dissolved. A positive color reproduction remained on the mordanted reception layer on the support.

Example 10 A mutlilayer photographic element suitable for use in preparing three-color diffusion transfer images was prepared by coating on a cellulose acetate film support the following layers numbered in sequence from the support:

(1) Blue-sensitive layer.A 5% coupler solution (0.005 mole), prepared by dissolving 4.3 g. of coupler I in 4.3 cc. of dimethylformamide and 43.0 cc. of 1% triethylamine, made up to a total weight of 86.5 g. with water was added to 200 g. of a 3% gelatin solution and the solution pH was adjusted to 6.3 with citric acid solution. The resultant gelatin solution was added to a portion of a blue-sensitive 2/98 silver chlorobromide-gelatin emulsion containing 0.06 mole of silver halide.

(2) Red-sensitive Iayer.A 5% coupler solution (0.0061 mole) prepared as in layer 1 but with coupler XV to a total weight of 86.5 g. with Water was prepared and added to a portion of a red-sensitized 80/20 silver chlorobromide-gelatin emulsion containing 0.06 mole of silver halide.

(3) Green-senstive layer.A 5% solution (0.0057 mole) of coupler XXX prepared and adjusted in the same manner as for layer 2 was added to a portion of a green-sensitive 80/20 chlorobromide-gelatin emulsion containing 0.06 mole of silver halide.

The respective emulsions were coated to give 100 mg. of coupler and 150 mg. of silver per square foot. Each emulsion was adjusted to a pH of 6.5 with a 2.5 N sodium hydroxide solution before coating. Negativetype developing-out emulsions were used in the emulsion layers. The resulting color film was exposed through a positive color transparency, developed in Black-and- White Developer E described above for 3 minutes at 70 F. and then reversal exposed with white light. The reversal exposed film was then immersed in Color Developer C described above together with a mordanted receiving sheet as described in Example 1 for seconds and the film and the receiving sheet were then sequeegeed together. After 7 minutes the receiving sheet was stripped 38 off and the receiving sheet carrying a positive r'eversal colored image was rinsed in 1% acetic acid solution followed by cold water and then dried.

Experiments were effected in which the sharpness of the dye images formed in the process described in Example 2 was analyzed by means of microdensitorneter tracings of the dye images of narrow lines. In these experiments the sharpness was defined from microdensitometry as the percent of the total dye in a line which was measured within the original exposure width. The sharpness was systematically altered by varying the diffusion path length using gelatin overcoats of varying thicknesses over the photographic element. The sharpness that was obtained on color developing the color film structure as described in Example 2 was significantly greater that which was predicted from mathematical calculations concerning the diffusion characteristics of the difiusible dyes in an isotropic gelatin media.

The present color process is also characterized as producing uniform color diffusion transfer images. The oxidation product of aromatic primary amino color developing agents contains, not only useful compounds that react with color couplers to form dyes, but also compounds that are development inhibitors. The effect of such development inhibitors is minimized in processes utilizing processing vessels, tanks and the like as the development inhibitors diffuse into such vehicles and their effect is diluted. Also, the effect of the development inhibitors would not be expected to be as significant with color processes utilizing single layer elements and highly reactive color couplers as the development inhibitors would have less of an opportunity to compete with the desired color coupling reaction. However, in accordance with the present invention, multilayer photographic elements containing at least three different color couplers having the coupling moiety blocked with a connecting radical (LINK described above) and which inherently have different reactivities can be utilized to produce highly uniform color diffusion transfer images even though a predominant proportion of the color development is effected in the presence of the oxidation product of the color developing agent.

The present invention thus provides new and useful photographic elements as well as new diffusion transfer processes for preparing color images from such photographic elements.

Although the invention has been described in detail with particular reference to certain typical embodiments thereof, it will be understood that variations and modifications can be effected within the spirit and scope of the invention as described hereinabove and as defined in the appended claims.

We claim:

1. A color photographic diffusion transfer process for color processing a light-sensitive photographic element having a pattern of developable silver halide comprising a support with superposed red, green and blue lightsensitive hydrophilic colloid-silver halide emulsions and having dispersed integral with said element and contiguous to said emulsions a cyanaforming coupler, a magentaforming coupler and a yellow-forming coupler, said couplers being nondiffusible during development in the presence of an alkaline color developing composition containing an aromatic primary amino color developing agent and containing substituents in their coupling positions that cleave off during the said color development forming diifusible acid dyes on reaction with color development oxidation product of said color developing agent; which process comprises treating said photographic element with said alkaline color developing composition and color developing said pattern of developable silver halide with a predominant proportion of the resulting oxidation product of said color developing agent remaining in said element during said developing, said 

1. A COLOR PHOTOGRAPHIC DIFFUSION TRANSFER PROCESS FOR COLOR PROCESSING A LIGHT-SENSITIVE PHOTOGRAPHIC ELEMENT HAVING A PATTERN OF DEVELOPABLE SILVER HALIDE COMPRISING A SUPPORT WITH SUPERPOSED RED, GREEN AND BLUE LIGHTSENSITIVE HYDROPHILIC COLLOID-SILVER HALIDE EMULSIONS AND HAVING DISPERSED INTEGRAL WITH SAID ELEMENT AND CONTIGUOUS TO SAID EMULSIONS A CYAN-FORMING COUPLER, A MAGENTAFORMING COUPLER AND A YELLOW-FORMING COUPLER, SAID COUPLERS BEING NONDIFFUSIBLE DURING DEVELOPMENT IN THE PRESENCE OF AN ALKALINE COLOR DEVELOPING COMPOSITION CONTAINING AN AROMATIC PRIMARY AMINO COLOR DEVELOPING AGENT AND CONTAINING SUBSTITUENTS IN THEIR COUPLING POSITIONS THAT CLEAVE OFF DURING THE SAID COLOR DEVELOPMENT FORMING DIFFUSIBLE ACID DYES ON REACTION WITH COLOR DEVELOPMENT OXIDATION PRODUCT OF SAID COLOR DEVELOPING AGENT; WHICH PROCESS COMPRISES TREATING SAID PHOTOGRAPHIC ELEMENT WITH SAID ALKALINE COLOR DEVELOPING COMPOSITION AND COLOR DEVELOPING SAID PATTERN OF DEVELOPABLE SILVER HALIDE WITH A PREDOMINANT PROPORTION OF THE RESULTING OXIDATION PRODUCT OF SAID COLOR DEVELOPING AGENT REMAINING IN SAID ELEMENT DURING SAID DEVELOPING, SAID COUPLERS COUPLING WITH OXIDATION PRODUCT OF SAID COLOR DEVELOPING AGENT DURING SAID COLOR DEVELOPMENT AND RELEASING DIFFUSIBLE ACID DYE IMAGES IN AREAS OF COLOR DEVELOPMENT, DURING THE COURSE OF SAID COLOR DEVELOPMENT SAID DYE IMAGES DIFFUSING IMAGEWISE IN REGISTER TO A JUXTAPOSED RECEPTION LAYER CONTAINING A BASIC MORDANT FOR ACID DYES. 